Silencing decoders

Adding sound to locomotives can get addictive, but once you have several sounding off at the same time in the same area of your layout the sounds can get to be annoying. To counter this, in addition to using F8 to mute sounds, most decoders now provide some way to silence decoders at startup or to automatically shut them off after a set period. I recently started putting together a listing of these options and here are the ones I could find something on.


The only thing I could find in the BLI manual was a way to silence the engine at startup. This is done by programming CV133 to a value of 0-255. A value of 0 will set the initial volume to completely off. Once you want sound turned on you can use F8 to increase sound volume in 8 increasing or decreasing steps. Hitting F8 once will mute sound and change from increasing it to decreasing it and vice versa. Hitting F8 twice will then step through 8 increments of volume. The amount of increase or decrease in sound volume depends on the sound increment set using CV130. The default value is 16.


Digitrax sound decoders use CV11 for a sound time out. With the default value of 06 locomotive sounds will turn off about 5 seconds after the locomotive is dispatched from a throttle. When reselected the sound will come back on. If CV11 is set to a value of 00 then sound will stay on when the loco is dispatched. If sound is off when the layout is powerd down it will also be off when power is turned back on.


Loksound Select decoders currently installed in Atlas locomotives by default have their sound turned on when power is turned on. You can set the decoder so that sound is off initially by programming CV32=2, CV403=16, and CV13=128. These values must be entered in exactly that order. Also some systems may not allow programming CVs greater than 255, requiring special programming steps. I will add a separate post later detailing those extra steps. If you have DecoderPro you can easily bypass this problem by using the CV pane to write these values.


MTH locomotives by default are silent on startup. When you want sound just hit F3 twice. Hitting F3 twice again will trigger the shutdown sequence.


With the Econami and Tsunami decoders Soundtraxx has a feature called Quiet Mode. By entering a value of 1-255 into CV113 you can set the amount of time it takes before the locomotive shuts down once the throttle is set to 0 and all functions turned off. The delay in seconds is calculated as CV113 x 0.25. So a value of 1 will specify a delay of 0.25 seconds and 255 will delay 63.75 seconds.


Like Loksound, TCS uses indexed CVs for many expanded functions, including Audio Auto Shutoff. Fortunately though their CVs for accessing indexed CVs are all less than 255 so shouldn’t require the extra steps that Loksound does. This is a two step process that uses CVs 201, 202, 203, and 204 for both steps. The first step is to activate the audio auto shutoff feature in User Options. Then you need to specify a time value for the automatic sound shutoff. Another feature found in the User Options is the ability to mute on startup. Refer to the sections in the diesel and steam WowSound user manuals for specifics on the values for these CVs. Also don’t forget that TCS has a CV calculator on their website to assit you in calculating values for these indexed CVs. If any of you find additional features that I missed please feel free to add them in a comment.


  • I have found that my BLI locomotives are silent when track power/signal comes up, No sound or function buttons until the throttle is advanced for the first time. I believe that’s the factory default setting with more recent production.

  • I use the Loksound V4 and Zimo docoders. With both of these, if you shut off the respective locomotive’s sound prior to shut down of the layout, the sound will remain off on power-up. This system works fine for me.

  • Thanks for the tip! Some locomotive manufacturers such as Walthers have the no frills sound decoders already installed and don’t have all the options. I have two of there GE Dash 8-40BW’s that have Soundtraxx decoders and they cannot be silenced.

    • Bob, that is definitely a situation where a toggle switch wired in line to a track feeder could be used to turn track power off to a holding track and kill the sound. I am wiring all my staging tracks so that track power is turned off automatically as soon as the lead loco nears the end of the track.